Field of the Invention
The invention relates in general to a mismatch processing technology, and more particularly, to a mismatch processing technology for processing in-phase and quadrature-phase (IQ) mismatch.
Description of the Related Art
Communication technologies adopting in-phase and quadrature-phase modulations (e.g, the orthogonal frequency division multiplexing (OFDM) communication technology) usually encounter in-phase and quadrature-phase (IQ) mismatch. To solve this problem, frequency-dependent gain and phase mismatch and frequency-independent gain and phase mismatch are often separately detected and compensated in the prior arts. The frequency-dependent mismatch is caused by a low-pass filter (LPF) in an in-phase signal transmission path and a LPF in a quadrature-phase signal transmission path. The frequency-independent mismatch is caused by a modulator in the in-phase signal transmission path and a modulator in the quadrature-phase signal transmission path.
In current technologies, the frequency-dependent mismatch and the frequency-independent mismatch are separated detected and compensated (e.g., the frequency-dependent mismatch is first detected and compensated, and the frequency-independent mismatch is then detected and compensated). Thus, the current technologies may not only consume more operation time but also suffer from certain issues such as sampling phase difference caused by mismatch.
For example, some details of the prior art may be referred from the U.S. Pat. No. 7,570,923.